Gas irradiation apparatus and method

ABSTRACT

A gas irradiation system has an irradiation chamber having a plurality of compartments disposed circumferentially about a central axis. One of the compartments is an inlet compartment. The inlet compartment has an aperture at the bottom through which gas flows from the compartment. The irradiation chamber comprises a plurality of UV lights which are configured to irradiate the gas and neutralize pathogens as the gas flows through the irradiation chamber. Circumferentially adjacent to one side of the inlet compartment is an outlet compartment. Circumferentially adjacent in the opposite circumferential direction on the other side of the inlet compartment is the first of a plurality of intermediate compartments. These intermediate compartments extend circumferentially about the central axis between the inlet compartment and the outlet compartment.

BACKGROUND OF THE INVENTION

The present invention generally relates to the treating gas toneutralize pathogens contained in the gas. More specifically,embodiments of the present invention relate to the neutralizing ofpathogens contained in air inhaled by humans. Embodiments of the presentinvention may also be utilized for treating the exhalations of personswho may be infected with pathogens, including viruses, bacteria, fungior other pathogens, where the exhalations may otherwise present apotential risk of harm to persons exposed to the exhalations. The recentand ongoing SARS-CoV-2 coronavirus epidemic has illustrated the need foreffective devices and methods which can provide safe breathing air forfirst responders, caregivers, and essential personnel. Such devices maybe configured into a package which is relatively small, lightweight,easy to use, and having self-contained power means. Alternatively, thedevices may be configured as part of a heating, ventilation, and airconditioning (“HVAC”) system for a building, vehicle, marine vessel oraircraft.

UVC light technology (“UV-C light”) is a radiation method which makesuse of specific wavelengths of ultraviolet light to neutralizepathogens. The wavelengths of UV-C light range from 200 to 300nanometers. UV-C light is germicidal, which means it deactivates the DNAof microorganisms such as bacteria, viruses, and other pathogens, whichdisrupt the ability of the microorganisms to multiply and cause disease.UV-C light having a wavelength of 190-290 nm has also been found to beeffective to inactivate spores of Bacillus anthracis. Given the robustnature of Bacillus anthracis and its relatively large single-cell size,an upstream filter should first be utilized. Once filtered, UV-C lightcan be effective in attacking the pathogen.

A variety of devices are known which utilize UV-C light for neutralizingpathogens. It is known that the level of neutralization of the pathogensis related to the exposure time of the pathogens to the UV-C light, andthe distance of the UV-C light to the pathogens. An apparatus whichprovides effective exposure time and distance to multiple sources ofUV-C light to a gas stream potentially carrying pathogens is desirable.It is also desirable that embodiments of such an apparatus areconfigurable as either a portable, lightweight, and self-containedsystem which may easily be carried and/or worn by first responders,caregivers, essential personnel, etc., or as components of an HVACsystem for processing air circulated within enclosed spaces.

It would also be desirable to have a device which may also be configuredto neutralize pathogens in the exhalations of an infected person,effectively quarantining the infected person from caregivers, familymembers and the like. Embodiments of the present invention provide ananswer to these needs.

SUMMARY OF THE INVENTION

Embodiments of the presently disclosed gas irradiation system may purifyincoming gas streams of pathogens and other biological material byutilizing UV LEDs as the gas stream flows through a plurality ofradially adjacent compartments. The UV LEDs have germicidal wavelengthsof 100-400 nm, and typically in the range of 100-280 nm. UV-C lighthaving a wavelength of 190-290 nm has also been found to be effective toinactivate spores of Bacillus anthracis.

In some embodiments of the ultraviolet irradiation units the incominggas stream is first filtered of air particulates, gases, vapors, and/orbiological material by passing air through a high efficiency particulateair (“HEPA”) filter to screen out particulates, gases, and vapors inaddition to the pathogens. A HEPA filter should first be utilized inapplications intended to inactivate Bacillus anthracis. Given the robustnature of Bacillus anthracis and its relatively large single-cell size,prefiltering an air stream containing this pathogen allows the UV-Clight to inactivate remaining cells.

An embodiment of the presently disclosed air irradiation system has anirradiation chamber comprising a plurality of compartments disposedcircumferentially about a central axis. Each compartment may have a topend and a bottom end. One of the compartments of the plurality ofcompartments is an inlet compartment and one of the compartments of theplurality of compartments is an outlet compartment which is radiallyadjacent to the inlet compartment. An inlet to the inlet compartmentprovides a conduit for a flow of a gas into the top end of the inletcompartment.

It is to be appreciated that because the apparatus is capable of reverseflow through the plurality of compartments, when the flow direction isreversed the “inlet” compartment will function as the “outlet”compartment and the “inlet” will function as an “outlet”.

The bottom end of the inlet compartment has an aperture through whichthe flow of gas exits the inlet compartment (or the flow of gas entersthe compartment in the case of reverse flow). Circumferentially adjacenton one side of the inlet compartment is an outlet compartment.Circumferentially adjacent in the opposite circumferential direction onthe other side of the inlet compartment is the first of a plurality ofintermediate compartments. These intermediate compartments extendcircumferentially about the central axis between the inlet compartmentand the outlet compartment. The compartments (inlet, outlet, andintermediate) have an open upper end and a bottom end. The bottom end ofeach compartment is sealed except for an aperture set within the bottomend to allow for gas to flow out of or into the compartment.

A plurality of UV LEDs having a germicidal wavelength of 100-400 nm,typically in the range of 100-280 nm, are disposed within theirradiation chamber and are configured to irradiate the flow of gaspassing through the irradiation chamber. The UV LEDS may be adjacent toone or more of the apertures. In some embodiments, a UV LED may bedisposed within or adjacent to each of the compartments. In otherembodiments, the UV LEDs may be disposed in several, but not all of thecompartments. For example, a UV LED may be disposed adjacent to eachcompartment, alternate compartments, every third compartment, or otherconfiguration.

In some embodiments the UV LEDs may be connected to a controller whichenergizes selected UV LEDS according to the irradiation requirements ofthe particular gas flowing through the irradiation chamber. In someembodiments an optional UVC transparent glass lens, such as onefabricated from quartz, may be placed over each UV LED.

A top cover or comparable structure seals over the top ends of thecompartments. The top cover has an underside having flow channels whichprovide for gas flow between the top ends of some pairs of adjacentcompartments. Each flow channel may include an O-ring seal whichencloses the flow channel to prevent intrusion of gas from other sourcesand to prevent release of gas from within the flow channel.

A bottom member seals over the bottom ends of the compartments, whereinthe bottom member has an upper side which seals flow channels betweenthe bottom ends of adjacent compartments. These flow channels may alsoutilize O-rings to prevent contamination or gas release.

Gas flow through the compartments may be driven by a pressuredifferential apparatus. In one embodiment of the apparatus, the pressuredifferential apparatus is a fan which is disposed upstream of the inletcompartment. Alternatively, the pressure differential apparatus may be avacuum fan attached to the outlet compartment. A HEPA filter may bedisposed upstream of the inlet compartment. For example, a positivepressure fan and filter may be placed immediately upstream of the inletto the inlet compartment. Alternatively, a filter may be placedimmediately upstream of the inlet to the inlet compartment and a vacuumfan connected to the outlet of the outlet compartment, with the vacuumfan applying a vacuum to all of the compartments.

In a normal flow operation, a flow of gas flows into and through theinlet compartment and exits the inlet compartment through the apertureat the bottom end. Upon exiting the inlet compartment, the flow of gaspasses through a flow channel between the bottom of the inletcompartment and a first intermediate compartment, where the flowchannels is sealed by the O-rings and structures of the bottom member.The flow of gas passes from the bottom to the top of the firstintermediate compartment. The flow of gas passes through the top end ofthe first intermediate compartment through an upper flow path into thetop of a circumferentially adjacent second intermediate compartment.Flow through the irradiation chamber proceeds sequentially through eachof the circumferentially adjacent intermediate compartments, whereirradiation may be applied to the flow gas stream at any point in theflow path, until the gas flows into the outlet compartment through theaperture at the bottom end of the outlet compartment and exits theirradiation chamber through the outlet at the upper end.

A reverse flow operation may be achieved by changing the direction of afan or other pressure differential apparatus. In the reverse flowoperation, the flow of gas enters the irradiation chamber through theoutlet compartment, flows sequentially through the intermediatecompartments in the same manner as discussed above, enters the inletcompartment at the aperture at the bottom end and exits the compartmentthrough the “inlet” at the upper end.

The UV LEDs may be attached to the cover, in the walls of thecompartments, or attached or disposed in the bottom member. The bottommember may also comprise a heat sink to dissipate the heat generatedfrom the UV LEDS. The irradiation chamber may comprise a heatdissipation fan to further provide for cooling of the UV LEDs.

Each of the compartments may be in a cylindrical configuration and theirradiation chamber itself may be cylindrical. The compartments may becircumferentially disposed about a cylindrical storage compartment. Apower source, such as a rechargeable battery, may be disposed within thecylindrical storage compartment. The UV LEDs, heat dissipation fan andthe pressure differential apparatus may receive power from the powersource.

The air irradiation system may further comprise a tube connected to theoutlet compartment and a face mask attached to the tube. The airirradiation system may be packaged in an easily transportable carryingcase for personal usage. Alternatively, embodiments of the irradiationchamber may be placed as a component of an HVAC system to purify an airstream being provided to an enclosure, such as a building, vehicle,marine vessel, or aircraft. In these applications, a plurality ofirradiation chambers may be disposed either in a series or parallelconfiguration to provide for a high volume of flow through the system asrequired for the building, vehicle, marine vessel, or aircraft.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a perspective view of an embodiment of an irradiationchamber utilized with the currently disclosed gas irradiation system.

FIG. 2 depicts a front view of the irradiation chamber shown in FIG. 1 .

FIG. 3 depicts a side view of the irradiation chamber shown in FIG. 1 .

FIG. 4 depicts a top view of the irradiation chamber shown in FIG. 1 .

FIG. 5 shows a sectional view along line 5-5 of FIG. 4 .

FIG. 5A shows a dimensioned sectional view for an embodiment of theirradiation chamber.

FIG. 5B depicts a dimensioned illumination profile within a compartmentof an embodiment of an irradiation chamber.

FIG. 6 depicts an exploded view of the irradiation chamber depicted inFIG. 1 .

FIG. 7 depicts a perspective bottom view of an embodiment of a cover forthe irradiation chamber depicted in FIG. 1 .

FIG. 8 depicts a top view of the cover for the irradiation chamberdepicted in FIG. 7 .

FIG. 9 depicts a bottom view of the cover for the irradiation chamberdepicted in FIG. 7 .

FIG. 10 shows a side view of the cover for the irradiation chamberdepicted in FIG. 7 .

FIG. 11 depicts a sectional view taken along line 11-11 of FIG. 8 .

FIG. 12 depicts a top perspective view of an embodiment of theirradiation chamber body showing a configuration of the compartmentsdisposed circumferentially about a central storage compartment.

FIG. 13 shows a top view of the embodiment of the irradiation chamberbody depicted in FIG. 12 .

FIG. 14 is a sectional view of the irradiation chamber body taken alongline 14-14 of FIG. 13 .

FIG. 15 depicts a bottom perspective view of the embodiment of theirradiation chamber body depicted in FIG. 12 .

FIG. 16 is a top perspective view of a bottom member which seals againstthe bottom of the housing of the irradiation chamber.

FIG. 17 is a top view of a bottom member which seals against the bottomof the housing of the irradiation chamber.

FIG. 18 is a sectional view of the bottom member taken along line 18-18of FIG. 17 .

FIG. 19 depicts an embodiment of enclosure which may be utilized tohouse and transport the irradiation chamber.

FIG. 20 depicts an embodiment of a personal breathing system of thepresently disclosed invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the Figures, FIG. 1 shows a perspective view of anembodiment of an irradiation chamber 100 which may be utilized with agas irradiation system. While the gas irradiation system will typicallybe packaged as a self-contained unit for use by individuals, it is to beappreciated that components of the system may be utilized forirradiating gas streams for other applications. For example, irradiationchambers 100 may be configured in an HVAC system to irradiate a gasstream for a room, building, vehicle, aircraft, or marine vessel. Insuch application, multiple irradiation chambers may be configured inseries or in parallel as required for the specific application. The term“gas” as used in the present disclosure will most typically be referringto atmospheric air. However, embodiments of the present invention may beutilized to neutralize pathogens in any gas stream.

As shown in FIGS. 1 through 4 , irradiation chamber 100 may be packagedin a generally cylindrical configuration. However, it is to beappreciated that non-cylindrical configurations compatible with thesequential compartment arrangement discussed below may also be utilized.Embodiments of the Irradiation chamber 100 may comprise a cover 102, ahousing 104, a bottom member 106, an inlet 108 and an outlet 110. Cover102 may be secured to housing 104 with screws or other attachment means.Likewise, housing 104 may be secured to bottom member 106 with threadedfasteners.

FIGS. 5 and 5A show sectional views along line 5-5 of FIG. 4 , showingthe abutting attachment of housing 104 to bottom member 106 whichcreates flow passages between adjacent compartments 112, which arepositioned circumferentially about axis A.

Irradiation chamber 100 may further comprise a cylindrical storagecompartment 142 about which compartments are positionedcircumferentially. Among other possible uses, cylindrical storagecompartment 142 may be utilized for storage of a power supply, such as abattery, for energizing a plurality of UV LEDS, a cooling fan, and/or apressure differential apparatus utilized to provide gas flow through theirradiation chamber 100. FIGS. 5 and 5A show a cooling fan 140 attachedto the underside of bottom member 106. The dimensions (in millimeters)shown in FIG. 5A depict an irradiation chamber which is sized to providean airflow rate suitable for the breathing requirements of a singleuser, typically about 8 liters of air per minute. However, dimensionsare provided for illustrative purpose only and are not intended in anyway to limit the configuration of any embodiment of the invention forany application.

For illustrative purposes, FIG. 5B depicts a dimensioned (inmillimeters) illumination profile for a UV LED 126 which may bepositioned at the bottom of a cylindrical compartment 112 within achamber of an embodiment of an irradiation chamber. FIG. 5B illustrateshow a gas flowing through an plurality of compartments may be exposed toUVC radiation in the illumination chamber.

FIG. 6 depicts an exploded view of an irradiation chamber 100 of anembodiment of the present invention, showing an embodiment of anarrangement of the compartments 112 within housing 104 as per thepresent invention. The irradiation chamber 100 depicted in FIG. 6comprises a plurality of compartments 112 which, as shown in FIG. 5 ,are disposed circumferentially about a central axis A which may comprisealso be the central axis for cylindrical storage compartment 142. Theplurality of compartments 112 includes an inlet compartment 112′ whichreceives an inflowing gas stream through inlet 108, and an outletcompartment 112″ which discharges an outflowing gas stream throughoutlet 110. As shown in the figures, inlet compartment 112′ and outletcompartment 112″ are circumferentially adjacent to one another. Theremaining intermediate compartments 112 are circumferentially disposedin the opposite circumferential direction between inlet compartment 112′and outlet compartment 112″.

A gas flowing through the irradiation chamber 100 flows sequentiallythrough all of the compartments of irradiation chamber 100 starting atinlet compartment 112′, through the plurality of intermediatecompartments 112, into the outlet compartment 112″ and flowing out ofthe irradiation chamber 100. The arrow on FIG. 13 shows the direction offlow beginning at compartment 112′ as a gas stream flowscounter-clockwise through the intermediate compartments 112 and arrivingat outlet compartment 112″. As the gas flows through the compartments,it is irradiated by a plurality of UV LEDs 126. As shown in FIG. 6 ,each compartment 112, 112′, 112″ may have a dedicated UV LED 126positioned immediately adjacent to the bottom end 116 of eachcompartment. Alternatively, the UV LEDs 126 may be placed in otherconfigurations, e.g. at every other compartment or set within the sidewalls of the compartments. Each UV LED 126 may be covered by aprotective lens 136 which will typically be fabricated from quartz.

Flow through irradiation chamber 100 may be reversed by changing thedirection of the pressure differential applied to the irradiationchamber, such that the gas flow enters the irradiation chamber 100through outlet 110 into outlet compartment 112″ through intermediatecompartments 112 into inlet compartment 112′ and exiting through inlet108.

As indicated in FIGS. 6 and 12 , the compartments 112 may be in acylindrical configuration. However, the compartments may be in anon-cylindrical configuration so long as the compartments are disposedcircumferentially about a central axis and configured such that gasflows sequentially through all of the intermediate compartments 112between the inlet compartment 112′ and the outlet chamber 112″

Each compartment 112 has an open top end 114 and a bottom end 116.Bottom end 116 is sealed except for an aperture 118 which penetratesthrough the bottom end 116 of each compartment 112 resulting in anopening in the underside of housing 104 as best shown in FIG. 15 . Asshown on FIG. 15 , adjacent pairs of apertures 118 are enclosed on theunderside of housing 104 by a seal wall 134 which may be generallyconfigured in the shape of a kidney. A flow of gas which enters throughinlet compartment 112′ will flow out through aperture 118′ and, becauseof the sealing of seal wall 134 by bottom member 106, will be directedto the circumferentially adjacent aperture 118 for entry into thecircumferentially adjacent intermediate compartment 112. FIG. 15indicates by the arrows the flow of gas between adjacent compartmentsuntil the gas flows into aperture 118″ of outlet i compartment 112″. Itis to be appreciated that in a reverse flow situation, the flow of gaswill be in the opposite direction indicated by the arrows shown in FIG.15 .

FIGS. 12 through 15 depict an embodiment of a housing 104 for theirradiation chamber 100. The open ends 114 of the compartments 112 aresealed by cover 102, an embodiment of which is shown in FIGS. 7 through11 . Cover 102 has an underside having flow channels 120 which allow gasflow between the top ends 114 of adjacent pairs of intermediatecompartments 112. Such flow channels 120 are depicted in FIGS. 7 and 9 .As also shown in FIGS. 7 and 9 , the underside of cover 102 has aninflow chamber 122 which covers the top end 114′ of inlet compartment112′ and an outflow chamber 124 which covers the top end 114″ of outletcompartment 112″. O-rings 132 may be utilized to increase the sealingaround flow channels 120, the inflow chamber 122, the outflow chamber114 which are utilized to convey gas flow between the open top ends 114of adjacent compartments.

The bottom ends 116 of compartments 112 are sealed off by bottom member106 depicted in FIGS. 16 through 18 . which seals against the bottom ofhousing 104 and seal walls 134. An embodiment of bottom member 106 isshown in greater detail in FIGS. 16 through 18 . Contoured O-ring groove130 defines a generally kidney-shaped footprint around adjacent seats128. O-rings 132′ are disposed within contoured O-ring grooves 130 toprevent gas flow except between adjacent compartments 112 in thesequence described above. Bottom member 106 is attached to housing 104such that aperture 118′ of the inlet compartment 112′ is positioneddirectly above seat 128′ shown in FIGS. 16-17 . When so positioned,aperture 118″ of the outlet compartment 112″ will be positioned directlyabove seat 128″. Because it is desirable that none of the gas enteringinlet compartment 112′ leaks into outlet compartment 112″, bottom member106 may further comprise seal structure 136, which allows separateO-rings (not shown) to be placed around the seats 128′, 128″.

As suggested by the above description, when bottom member 106 isattached to the bottom of housing 104, seal walls 134 do not align withthe generally kidney-shaped O-ring grooves around adjacent seats 128,but rather overlap.

Bottom member 106 may be utilized as a platform for UV LEDs 126 whichmay be seated in seats 128 of an upper side of bottom member 106. Inorder to redirect heat away from UV LEDs 126, bottom member 106 may befabricated from a heat sink material such as copper or aluminum. Bottommember 106 may be fabricated with screw holes for retaining UV LEDs tothe bottom member. Bottom member 106 may also have openings adjacent toseats 128 for running electrical leads and/or control wires to the UVLEDs 126.

FIG. 19 depicts a housing 138 which may be utilized to containembodiments of irradiation chamber 100, showing an outlet 140 whichreceives irradiated gas from outlet 108 of the irradiation chamber. Inaddition to irradiation chamber 100, housing 138 may also contain apressure differential apparatus, such as a positive pressure fan orvacuum fan for applying a pressure differential to irradiation chamber100 to drive a gas flow through the irradiation chamber. Housing 138 mayalso contain a HEPA filter and filter carrier utilized to filter a gasentering the irradiation chamber. As indicated above, the flow directionthrough the irradiation chamber 100 may be reversed by changing thedirection of the fan. In reverse flow operations, outlet 140 may beutilized to provide an inflow to the irradiation chamber.

FIG. 20 depicts an embodiment of a personal breathing system 150 of thepresently disclosed invention which combines the irradiation chamber 100contained within housing 138. A hose 142 is attached to outlet 140 ofthe housing 138 and a mask 144 attached to the hose. In reverse flowoperation, exhalations containing pathogens may be directed into mask144 and conveyed by hose 142 to the irradiation chamber 100 contained inthe housing 138.

Having thus described the preferred embodiment of the invention, what isclaimed as new and desired to be protected by Letters Patent includesthe following:
 1. A gas irradiation system comprising: a housing membercomprising a plurality of compartments disposed circumferentially abouta central axis, the plurality of compartments comprising an inletcompartment, an outlet compartment, and a plurality of intermediatecompartments disposed circumferentially between the inlet compartmentand the outlet compartment, each compartment comprising an open top endand a bottom end, each bottom end comprising an aperture whichpenetrates the bottom end to form an opening for each compartment in anunderside of the housing member; a cover which seals the open top endsof the compartments, wherein the cover has an underside having a flowchannel configured to provide an upper flow path between the top ends ofan adjacent pair of compartments; a bottom member having an upper sideconfigured to provide a lower flow path between the bottom ends of anadjacent pair of compartments; a plurality of light emitting diodesconfigured to irradiate a flow of gas as the flow of gas passes throughthe compartments; wherein the upper flow path and the lower flow pathare configured such that the flow of gas passes sequentially through theinlet compartment, through the plurality of intermediate compartments,into the outlet compartment.
 2. The gas irradiation system of claim 1wherein the underside comprises a seal wall which encloses the openingsof adjacent compartments, the seal wall providing the lower flow pathbetween the adjacent compartments.
 3. The gas irradiation system ofclaim 2 wherein the light emitting diodes are mounted to the bottommember.
 4. The gas irradiation system of claim 3 wherein the bottommember comprises a heat sink.
 5. The gas irradiation system of claim 4further comprising a heat dissipation fan attached to the bottom member.6. The gas irradiation system of claim 1 wherein each of thecompartments are cylindrical.
 7. The gas irradiation system of claim 1further comprising a tube connected to the oulet compartment.
 8. The gasirradiation system of claim 7 further comprising a face mask attached tothe tube.
 9. The gas irradiation system of claim 1 wherein the housingis cylindrical.
 10. The gas irradiation system of claim 1 wherein theplurality of compartments are disposed about a cylindrical housing. 11.The air irradiation system of claim 10 wherein the power source isdisposed within the cylindrical housing.
 12. A gas irradiation systemcomprising: a housing comprising a central axis, the housing furthercomprising a plurality of compartments, the plurality of compartmentsindividually disposed in a circumferential configuration about thecentral axis, the plurality of compartments comprising an inletcompartment and a circumferentially adjacent outlet compartment on afirst side of the inlet compartment, and a plurality of intermediatecompartments extending circumferentially between a second side of theinlet compartment and the outlet compartment; and a plurality ofultraviolet light emitting diodes, wherein each of the ultraviolet lightemitting diodes of the plurality of ultraviolet light emitting diodes isconfigured to progressively irradiate a flow of gas as it sequentiallyflows through the inlet compartment, the intermediate compartments, andthe outlet compartment.
 13. The gas irradiation system of claim 11wherein each of the plurality of compartments is cylindrical.
 14. Thegas irradiation system of claim 12 further comprising a bottom memberwhich attaches to a bottom end of each of the compartments of theplurality of compartments, wherein a flow channel is defined between thebottom ends of adjacent compartments and the bottom member, the flowchannel configured to direct the flow of gas between adjacentcompartments.
 15. The gas irradiation system of claim 14 wherein theplurality of light emitting diodes are mounted to the bottom member. 16.The gas irradiation system of claim 12 wherein the plurality ofcompartments configured such that the flow of gas sequentially flows:(i) from a top of the inlet compartment to a bottom of the inletcompartment, (ii) into a bottom of a circumferentially adjacent firstintermediate compartment to a top of the first intermediate compartment,(iii) into a top of a circumferentially adjacent second intermediatecompartment to a bottom of the second intermediate circumferentiallyadjacent compartment, (iv) into a bottom of a third intermediateirradiation compartment to a top of the third intermediate irradiationcompartment, (v) into the top of a circumferentially adjacent fourthintermediate irradiation compartment to the bottom of the fourthintermediate irradiation compartment, and (vi) into a bottom of thecircumferentially adjacent outlet compartment to a top of the outletcompartment, the flow of gas exiting the outlet compartment through anoutlet.
 17. The gas irradiation system of claim 12 further comprising atube connected to the outlet compartment.
 18. The gas irradiation systemof claim 17 further comprising a face mask attached to the tube.
 19. Amethod of irradiating a stream of gas comprising the following steps:directing the gas into an inlet of a housing, the housing comprising aplurality of compartments, the plurality of compartments individuallydisposed in a circumferential configuration about a central axis, theplurality of compartments comprising an inlet compartment and acircumferentially adjacent outlet compartment on a first side of theinlet compartment, and a plurality of intermediate compartmentsextending circumferentially between a second side of the inletcompartment and the outlet compartment; and energizing a plurality ofultraviolet light emitting diodes, wherein the plurality of ultravioletlight emitting diodes is configured to progressively irradiate the flowof gas as the gas sequentially flows through the inlet compartment, theintermediate compartments, and the outlet compartment resulting in flowof an irradiated gas stream to an outlet of the outlet compartment. 20.The method of claim 19 wherein the plurality of compartments areconfigured such that the flow of gas sequentially flows: (i) from a topof the inlet compartment to a bottom of the inlet compartment, (ii) intoa bottom of a circumferentially adjacent first intermediate compartmentto a top of the first intermediate irradiation compartment, (iii) into atop of a circumferentially adjacent second intermediate compartment tothe bottom of the second intermediate compartment, (iv) into a bottom ofa circumferentially adjacent third intermediate compartment to a top ofthe third intermediate irradiation compartment, (v) into a top of acircumferentially adjacent fourth intermediate compartment to a bottomof the fourth intermediate compartment, and (vi) into a bottom of thecircumferentially adjacent outlet compartment to a top of the outletcompartment, the flow of gas exiting the outlet compartment through anoutlet.